2008-03-31 Cary Coutant <ccoutant@google.com>

Add thin archive support.
	* archive.cc (Archive::armagt): New const.
	(Archive::setup): Remove task parameter and calls to unlock.
	(Archive::unlock_nested_archives): New function.
	(Archive::read_header): Add nested_off parameter. Change
	all callers.
	(Archive::interpret_header): Likewise.
	(Archive::include_all_members): Change to handle thin
	archives.
	(Archive::include_member): Likewise.
	* archive.h (Archive::Archive): Add new parameters and
	initializers.
	(Archive::armagt): New const.
	(Archive::setup): Remove task parameter.
	(Archive::unlock_nested_archives): New function.
	(Archive::read_header): Add nested_off parameter.
	(Archive::interpret_header): Likewise.
	(Archive::Nested_archive_table): New typedef.
	(Archive::is_thin_archive_): New field.
	(Archive::nested_archives_): New field.
	(Archive::options_): New field.
	(Archive::dirpath_): New field.
	(Archive::task_): New field.
	* readsyms.cc (Read_symbols::do_read_symbols): Add check
	for thin archives.  Pass additional parameters to
	Archive::Archive.  Unlock the archive file after calling
	Archive::setup.
This commit is contained in:
Cary Coutant 2008-04-01 20:57:36 +00:00
parent 79c6ced6ea
commit a12074662b
4 changed files with 178 additions and 30 deletions

View file

@ -1,3 +1,33 @@
2008-03-31 Cary Coutant <ccoutant@google.com>
Add thin archive support.
* archive.cc (Archive::armagt): New const.
(Archive::setup): Remove task parameter and calls to unlock.
(Archive::unlock_nested_archives): New function.
(Archive::read_header): Add nested_off parameter. Change
all callers.
(Archive::interpret_header): Likewise.
(Archive::include_all_members): Change to handle thin
archives.
(Archive::include_member): Likewise.
* archive.h (Archive::Archive): Add new parameters and
initializers.
(Archive::armagt): New const.
(Archive::setup): Remove task parameter.
(Archive::unlock_nested_archives): New function.
(Archive::read_header): Add nested_off parameter.
(Archive::interpret_header): Likewise.
(Archive::Nested_archive_table): New typedef.
(Archive::is_thin_archive_): New field.
(Archive::nested_archives_): New field.
(Archive::options_): New field.
(Archive::dirpath_): New field.
(Archive::task_): New field.
* readsyms.cc (Read_symbols::do_read_symbols): Add check
for thin archives. Pass additional parameters to
Archive::Archive. Unlock the archive file after calling
Archive::setup.
2008-03-29 Ian Lance Taylor <iant@google.com>
* symtab.cc (Symbol_table::do_define_as_constant): Don't force a

View file

@ -26,6 +26,8 @@
#include <cstring>
#include <climits>
#include <vector>
#include "libiberty.h"
#include "filenames.h"
#include "elfcpp.h"
#include "options.h"
@ -67,26 +69,28 @@ const char Archive::armag[sarmag] =
'!', '<', 'a', 'r', 'c', 'h', '>', '\n'
};
const char Archive::armagt[sarmag] =
{
'!', '<', 't', 'h', 'i', 'n', '>', '\n'
};
const char Archive::arfmag[2] = { '`', '\n' };
// Set up the archive: read the symbol map and the extended name
// table.
void
Archive::setup(Task* task)
Archive::setup()
{
// We need to ignore empty archives.
if (this->input_file_->file().filesize() == sarmag)
{
this->input_file_->file().unlock(task);
return;
}
return;
// The first member of the archive should be the symbol table.
std::string armap_name;
section_size_type armap_size =
convert_to_section_size_type(this->read_header(sarmag, false,
&armap_name));
&armap_name, NULL));
off_t off = sarmag;
if (armap_name.empty())
{
@ -104,7 +108,7 @@ Archive::setup(Task* task)
++off;
std::string xname;
section_size_type extended_size =
convert_to_section_size_type(this->read_header(off, true, &xname));
convert_to_section_size_type(this->read_header(off, true, &xname, NULL));
if (xname == "/")
{
const unsigned char* p = this->get_view(off + sizeof(Archive_header),
@ -112,9 +116,19 @@ Archive::setup(Task* task)
const char* px = reinterpret_cast<const char*>(p);
this->extended_names_.assign(px, extended_size);
}
}
// Opening the file locked it. Unlock it now.
this->input_file_->file().unlock(task);
// Unlock any nested archives.
void
Archive::unlock_nested_archives()
{
for (Nested_archive_table::iterator p = this->nested_archives_.begin();
p != this->nested_archives_.end();
++p)
{
p->second->unlock(this->task_);
}
}
// Read the archive symbol map.
@ -161,11 +175,12 @@ Archive::read_armap(off_t start, section_size_type size)
// of the member.
off_t
Archive::read_header(off_t off, bool cache, std::string* pname)
Archive::read_header(off_t off, bool cache, std::string* pname,
off_t* nested_off)
{
const unsigned char* p = this->get_view(off, sizeof(Archive_header), cache);
const Archive_header* hdr = reinterpret_cast<const Archive_header*>(p);
return this->interpret_header(hdr, off, pname);
return this->interpret_header(hdr, off, pname, nested_off);
}
// Interpret the header of HDR, the header of the archive member at
@ -174,7 +189,7 @@ Archive::read_header(off_t off, bool cache, std::string* pname)
off_t
Archive::interpret_header(const Archive_header* hdr, off_t off,
std::string* pname)
std::string* pname, off_t* nested_off)
{
if (memcmp(hdr->ar_fmag, arfmag, sizeof arfmag) != 0)
{
@ -214,6 +229,8 @@ Archive::interpret_header(const Archive_header* hdr, off_t off,
return this->input_file_->file().filesize() - off;
}
pname->assign(hdr->ar_name, name_end - hdr->ar_name);
if (nested_off != NULL)
*nested_off = 0;
}
else if (hdr->ar_name[1] == ' ')
{
@ -229,6 +246,9 @@ Archive::interpret_header(const Archive_header* hdr, off_t off,
{
errno = 0;
long x = strtol(hdr->ar_name + 1, &end, 10);
long y = 0;
if (*end == ':')
y = strtol(end + 1, &end, 10);
if (*end != ' '
|| x < 0
|| (x == LONG_MAX && errno == ERANGE)
@ -240,15 +260,17 @@ Archive::interpret_header(const Archive_header* hdr, off_t off,
}
const char* name = this->extended_names_.data() + x;
const char* name_end = strchr(name, '/');
const char* name_end = strchr(name, '\n');
if (static_cast<size_t>(name_end - name) > this->extended_names_.size()
|| name_end[1] != '\n')
|| name_end[-1] != '/')
{
gold_error(_("%s: bad extended name entry at header %zu"),
this->name().c_str(), static_cast<size_t>(off));
return this->input_file_->file().filesize() - off;
}
pname->assign(name, name_end - name);
pname->assign(name, name_end - 1 - name);
if (nested_off != NULL)
*nested_off = y;
}
return member_size;
@ -348,7 +370,7 @@ Archive::include_all_members(Symbol_table* symtab, Layout* layout,
const Archive_header* hdr =
reinterpret_cast<const Archive_header*>(hdr_buf);
std::string name;
off_t size = this->interpret_header(hdr, off, &name);
off_t size = this->interpret_header(hdr, off, &name, NULL);
if (name.empty())
{
// Symbol table.
@ -360,7 +382,9 @@ Archive::include_all_members(Symbol_table* symtab, Layout* layout,
else
this->include_member(symtab, layout, input_objects, off);
off += sizeof(Archive_header) + size;
off += sizeof(Archive_header);
if (!this->is_thin_archive_)
off += size;
if ((off & 1) != 0)
++off;
}
@ -374,14 +398,75 @@ Archive::include_member(Symbol_table* symtab, Layout* layout,
Input_objects* input_objects, off_t off)
{
std::string n;
this->read_header(off, false, &n);
off_t nested_off;
this->read_header(off, false, &n, &nested_off);
const off_t memoff = off + static_cast<off_t>(sizeof(Archive_header));
Input_file* input_file;
off_t memoff;
if (!this->is_thin_archive_)
{
input_file = this->input_file_;
memoff = off + static_cast<off_t>(sizeof(Archive_header));
}
else
{
// Adjust a relative pathname so that it is relative
// to the directory containing the archive.
if (!IS_ABSOLUTE_PATH(n.c_str()))
{
const char *arch_path = this->name().c_str();
const char *basename = lbasename(arch_path);
if (basename > arch_path)
n.replace(0, 0, this->name().substr(0, basename - arch_path));
}
if (nested_off > 0)
{
// This is a member of a nested archive. Open the containing
// archive if we don't already have it open, then do a recursive
// call to include the member from that archive.
Archive* arch;
Nested_archive_table::const_iterator p =
this->nested_archives_.find(n);
if (p != this->nested_archives_.end())
arch = p->second;
else
{
Input_file_argument* input_file_arg =
new Input_file_argument(n.c_str(), false, "", false,
parameters->options());
input_file = new Input_file(input_file_arg);
if (!input_file->open(parameters->options(), *this->dirpath_,
this->task_))
return;
arch = new Archive(n, input_file, false, this->dirpath_,
this->task_);
arch->setup();
std::pair<Nested_archive_table::iterator, bool> ins =
this->nested_archives_.insert(std::make_pair(n, arch));
gold_assert(ins.second);
}
arch->include_member(symtab, layout, input_objects, nested_off);
return;
}
// This is an external member of a thin archive. Open the
// file as a regular relocatable object file.
Input_file_argument* input_file_arg =
new Input_file_argument(n.c_str(), false, "", false,
this->input_file_->options());
input_file = new Input_file(input_file_arg);
if (!input_file->open(parameters->options(), *this->dirpath_,
this->task_))
{
return;
}
memoff = 0;
}
// Read enough of the file to pick up the entire ELF header.
unsigned char ehdr_buf[elfcpp::Elf_sizes<64>::ehdr_size];
off_t filesize = this->input_file_->file().filesize();
off_t filesize = input_file->file().filesize();
int read_size = elfcpp::Elf_sizes<64>::ehdr_size;
if (filesize - memoff < read_size)
read_size = filesize - memoff;
@ -393,7 +478,7 @@ Archive::include_member(Symbol_table* symtab, Layout* layout,
return;
}
this->input_file_->file().read(memoff, read_size, ehdr_buf);
input_file->file().read(memoff, read_size, ehdr_buf);
static unsigned char elfmagic[4] =
{
@ -409,7 +494,7 @@ Archive::include_member(Symbol_table* symtab, Layout* layout,
Object* obj = make_elf_object((std::string(this->input_file_->filename())
+ "(" + n + ")"),
this->input_file_, memoff, ehdr_buf,
input_file, memoff, ehdr_buf,
read_size);
if (input_objects->add_object(obj))
@ -425,6 +510,11 @@ Archive::include_member(Symbol_table* symtab, Layout* layout,
delete obj;
}
if (this->is_thin_archive_)
{
// Opening the file locked it. Unlock it now.
input_file->file().unlock(this->task_);
}
}
// Add_archive_symbols methods.
@ -461,6 +551,8 @@ Add_archive_symbols::run(Workqueue*)
this->archive_->add_symbols(this->symtab_, this->layout_,
this->input_objects_);
this->archive_->unlock_nested_archives();
this->archive_->release();
if (this->input_group_ != NULL)

View file

@ -44,9 +44,11 @@ class Symbol_table;
class Archive
{
public:
Archive(const std::string& name, Input_file* input_file)
Archive(const std::string& name, Input_file* input_file,
bool is_thin_archive, Dirsearch* dirpath, Task* task)
: name_(name), input_file_(input_file), armap_(), armap_names_(),
extended_names_(), armap_checked_(), seen_offsets_()
extended_names_(), armap_checked_(), seen_offsets_(),
is_thin_archive_(is_thin_archive), dirpath_(dirpath), task_(task)
{ }
// The length of the magic string at the start of an archive.
@ -54,6 +56,7 @@ class Archive
// The magic string at the start of an archive.
static const char armag[sarmag];
static const char armagt[sarmag];
// The string expected at the end of an archive member header.
static const char arfmag[2];
@ -65,7 +68,7 @@ class Archive
// Set up the archive: read the symbol map.
void
setup(Task*);
setup();
// Get a reference to the underlying file.
File_read&
@ -97,6 +100,10 @@ class Archive
release()
{ this->input_file_->file().release(); }
// Unlock any nested archives.
void
unlock_nested_archives();
// Select members from the archive as needed and add them to the
// link.
void
@ -121,12 +128,13 @@ class Archive
// the file view. Return the size of the member, and set *PNAME to
// the name.
off_t
read_header(off_t off, bool cache, std::string* pname);
read_header(off_t off, bool cache, std::string* pname, off_t* nested_off);
// Interpret an archive header HDR at OFF. Return the size of the
// member, and set *PNAME to the name.
off_t
interpret_header(const Archive_header* hdr, off_t off, std::string* pname);
interpret_header(const Archive_header* hdr, off_t off, std::string* pname,
off_t* nested_off);
// Include all the archive members in the link.
void
@ -153,6 +161,9 @@ class Archive
{ return static_cast<size_t>(val); }
};
// For keeping track of open nested archives in a thin archive file.
typedef Unordered_map<std::string, Archive*> Nested_archive_table;
// Name of object as printed to user.
std::string name_;
// For reading the file.
@ -168,6 +179,14 @@ class Archive
std::vector<bool> armap_checked_;
// Track which elements have been included by offset.
Unordered_set<off_t, Seen_hash> seen_offsets_;
// True if this is a thin archive.
const bool is_thin_archive_;
// Table of nested archives, indexed by filename.
Nested_archive_table nested_archives_;
// The directory search path.
Dirsearch* dirpath_;
// The task reading this archive.
Task *task_;
};
// This class is used to read an archive and pick out the desired

View file

@ -204,12 +204,19 @@ Read_symbols::do_read_symbols(Workqueue* workqueue)
if (read_size >= Archive::sarmag)
{
if (memcmp(ehdr_buf, Archive::armag, Archive::sarmag) == 0)
bool is_thin_archive
= memcmp(ehdr_buf, Archive::armagt, Archive::sarmag) == 0;
if (is_thin_archive
|| memcmp(ehdr_buf, Archive::armag, Archive::sarmag) == 0)
{
// This is an archive.
Archive* arch = new Archive(this->input_argument_->file().name(),
input_file);
arch->setup(this);
input_file, is_thin_archive,
this->dirpath_, this);
arch->setup();
// Unlock the archive so it can be used in the next task.
arch->unlock(this);
workqueue->queue_next(new Add_archive_symbols(this->symtab_,
this->layout_,